go - 无法使用带有 BurntSushi 库的 Go 读取 TOML 文件

Question

我正在使用 BurntSushi 库在我的 GO 应用程序中加载 TOML 配置文件。我已按照库中的说明编写结构和配置 toml 文件本身。我遇到了一些麻烦，而且我似乎找不到问题的根源。

详情如下:

结构:

package main


//ConfigurationParameters provides the struct to hold configuration parameters from config file
type ConfigurationParameters struct {
    Title string
    //serviceDiscovery captures configuration parameters needed for service discovery registration with Consul
    ServiceDiscovery ConsulConf `toml:"ServiceDiscovery"`
    //metadataReporting captures which metadata to be registered with service into consul for use during discovery
    MetadataReporting MetaDataConf `toml:"MetadataReporting"`
    //awsTagsToLabels captures the aws tags that should be added to reported metrics as Labels
    AwsTagsToLabels LabelConf `toml:"AwsTagsToLabels"`
    //collectors captures the list of collectors to use
    Collectors CollectorConf `toml:"Collectors"`
    //service captures agent related configurations
    Service ServiceConf `toml:"Service"`
}

//ConsulConf captures configuration parameters needed for service discovery registration with Consul
type ConsulConf struct {
    enabled    bool
    endpoint   string
    port       int
    datacenter string
    serviceID  string
}
//MetaDataConf captures which metadata to be registered with service into consul for use during discovery
    type MetaDataConf struct {
        enabled   bool
        awsregion string
    }
//LabelConf captures the aws tags that should be added to reported metrics as Labels
type LabelConf struct {
    enabled       bool
    refreshPeriod int
}

//CollectorConf captures the list of collectors to use
type CollectorConf struct {
    goCollectionEnabled       bool
    exporterCollectionEnabled bool
    wmiCollectionEnabled      bool
    agentCollectionEnabled    bool
    enabledCollectors         string
    metricMap                 []MetricMap
}

//MetricMap captures a mapping between one or more WMI metrics and the name it should be reported with
type MetricMap struct {
    wmiMetricName  []string
    exportName     string
    dropMetric     bool
    computedMetric bool
    computeLogic   string
}

//ServiceConf captures agent related configurations
type ServiceConf struct {
    listenIP           string
    listenPort         int
    metricPath         string
    collectionInterval int
    serviceName        string
}

和配置toml文件:

Title = "WMI Exporter Configuration"

[ServiceDiscovery]
    enabled = true
    endpoint = "my.consul.server"
    port = 5500
    datacenter = "ucm-west"
    serviceID = "ucm.agent.wmiExporter"

[MetadataReporting]
    enabled = true
    awsregion = "us-west-2"

[AwsTagsToLabels]
    enabled = true
    refreshPeriod = 3600

[Collectors]
    goCollectionEnabled = true
    exporterCollectionEnabled = true
    wmiCollectionEnabled = true
    agentCollectionEnabled = false
    enabledCollectors   = "cpu,os"
    [Collectors.MetricMap.0]
        wmiMetricName = ["test"]
        exportName = "export_test"

[Service]
    listenPort =  9103
    metricPath = "/metrics"
    collectionInterval = 60
    serviceName = "wmi_exporter"

读取配置文件的代码:

// InitializeFromConfig reads configuration parameters from configuration file and initializes this service
func InitializeFromConfig(configfile string) ConfigurationParameters {
    conf := ConfigurationParameters{}

    if configfile == "" {
        return conf
    }

    _, err := toml.DecodeFile(configfile, &conf)
    if err != nil {
        log.Fatalf("Cannot parse configuration file at %s. Error=%s", configfile, err)
    }
    //at this point, conf is a fully loaded configuration now; now initialize everything from conf
    return conf
}

我面临的问题是只有 Title 属性的值被映射到 GO 结构成员。所有其他配置保持未映射状态。查看 github 上关于 BurntSushi 和 (Go) How to use toml files? 的所有示例，我看不出我目前在代码中所做的有什么不同。

我还使用了 BurntSushi 包中的 tomlv 验证器来查看 TOML 文件中的类型，我相信它们看起来是正确的。

数据类型:

Title                                             String
ServiceDiscovery                                  Hash
    ServiceDiscovery.enabled                      Bool
    ServiceDiscovery.endpoint                     String
    ServiceDiscovery.port                         Integer
    ServiceDiscovery.datacenter                   String
    ServiceDiscovery.serviceID                    String
MetadataReporting                                 Hash
    MetadataReporting.enabled                     Bool
    MetadataReporting.awsregion                   String
AwsTagsToLabels                                   Hash
    AwsTagsToLabels.enabled                       Bool
    AwsTagsToLabels.refreshPeriod                 Integer
Collectors                                        Hash
    Collectors.goCollectionEnabled                Bool
    Collectors.exporterCollectionEnabled          Bool
    Collectors.wmiCollectionEnabled               Bool
    Collectors.agentCollectionEnabled             Bool
    Collectors.enabledCollectors                  String
        Collectors.MetricMap.0                    Hash
            Collectors.MetricMap.0.wmiMetricName  Array
            Collectors.MetricMap.0.exportName     String
Service                                           Hash
    Service.listenPort                            Integer
    Service.metricPath                            String
    Service.collectionInterval                    Integer
    Service.serviceName                           String

我尝试调试 BurntSushi 包代码，但它不是很有帮助(Delve 调试器无法显示该包中的某些变量，并且似乎在该包中的行之间随机跳转)。

关于我可能做错了什么的任何帮助或指示？

谢谢。

Answer 1

您需要导出您希望 BurntSushi/toml 解码到的任何字段，包括子字段:

//ConfigurationParameters provides the struct to hold configuration parameters from config file
type ConfigurationParameters struct {
    Title string
    //serviceDiscovery captures configuration parameters needed for service discovery registration with Consul
    ServiceDiscovery ConsulConf `toml:"ServiceDiscovery"`
    //metadataReporting captures which metadata to be registered with service into consul for use during discovery
    MetadataReporting MetaDataConf `toml:"MetadataReporting"`
    //awsTagsToLabels captures the aws tags that should be added to reported metrics as Labels
    AwsTagsToLabels LabelConf `toml:"AwsTagsToLabels"`
    //collectors captures the list of collectors to use
    Collectors CollectorConf `toml:"Collectors"`
    //service captures agent related configurations
    Service ServiceConf `toml:"Service"`
}

//ConsulConf captures configuration parameters needed for service discovery registration with Consul
type ConsulConf struct {
    Enabled    bool
    Endpoint   string
    Port       int
    Datacenter string
    ServiceID  string
}

//MetaDataConf captures which metadata to be registered with service into consul for use during discovery
type MetaDataConf struct {
    Enabled   bool
    Awsregion string
}

//LabelConf captures the aws tags that should be added to reported metrics as Labels
type LabelConf struct {
    Enabled       bool
    RefreshPeriod int
}

//CollectorConf captures the list of collectors to use
type CollectorConf struct {
    GoCollectionEnabled       bool
    ExporterCollectionEnabled bool
    WmiCollectionEnabled      bool
    AgentCollectionEnabled    bool
    EnabledCollectors         string
    MetricMap                 []MetricMap
}

//MetricMap captures a mapping between one or more WMI metrics and the name it should be reported with
type MetricMap struct {
    WmiMetricName  []string
    ExportName     string
    DropMetric     bool
    ComputedMetric bool
    ComputeLogic   string
}

//ServiceConf captures agent related configurations
type ServiceConf struct {
    ListenIP           string
    ListenPort         int
    MetricPath         string
    CollectionInterval int
    ServiceName        string
}

此外，我不确定此 Collectors.MetricMap.0 语法应该表示什么，而是将您的 toml 值解码到 []MetricMap 字段中 你想要做的是这样的:

[[Collectors.MetricMap]]
    wmiMetricName = ["test"]
    exportName = "export_test"